Bette b



(No Model.

B. EQJ. EILS.

QUADRUPLEX TELEGRAPH.

Patented Sept. 30, 1884.

N PETERs wnwn wo. mt.

rricm BETTE E. J. EILS, OF WASHINGTON, DISTRICT OF COLUMBIA.

QUADRUPLEXTELEGRAPH.

LL LJOIFICATION' forming part of Letters Patent No. 305,907, datedSeptember 30, 1884.

Application filed February 19, 1884. No model.)

' To all whom it may concern:

Be it known that I, BETTE E. J. EILs, a citizen of the United States,residing at Wash- 'ington, in the District of Columbia, have in ventedcertain new and useful Improvements in Quadruplex Telegraphs; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled'in the art to whichitappertains to make and use the same.

This invention was primarily designed to adapt the invention describedin my application forUnited States Letters Patent, filed January 28,1884, Serial N 0. 118,999, for use on the neutral side of such diplex orquadruplex or multiplex telegraphs in which one message is received t-hiough a neutral relay subject to rise and fall of tension as well as toreversals of a normal line-current, and where the static dis charge ofthe line or any other cause increases the period of momentarydemagnetization of such relay during the reversals of the linecurrent tosuch an extent that the invention described in my aforesaid applicationcannot wholly bridge over such lengthened period of demagnetization.

My improvement consists in employing as part of the second local branchused for discharging the soundermagnet at the termination of eachsignal, as described in my afore said application, thefrontcontuct-screw and armature-lever of a subsidiary neutral relay inthe linecircuit, the said armature-lever of which is held against thesaid front contactscrew under all line-currents, but is momentarilyretracted during. reversals of lhe linecurrent, so as to break saidbranch during the period of demagnetization of the neutralreceiving-relay, and thus prevent the discharge of the sounderelectromaguet at times when a reversal occurs while the sounder ismaking a signal. 7

The annexed drawing is a diagram illustrating the embodiment of myimprovement in the well-known diplex telegraph, where one message istransmitted by rise and fall of tension of a normal line-current andreceived through a neutral receivingrelay, NR, and- My invention differsfrom the previouslyknown dipleX telegraph of this character solely inthe organization of the local circuit of the neutral receiving-relay,and further description may be confined to this new organization,because the general construction and mode of operation of the diplextelegraph illustrated will be readily understood from the diagram by anyoneskilled in the art.

The relay NR has a front contactscrew, a", and a back contact-screw, at,which contactscrews are insulated from each other, and between whichthearmature-lever a of the relay plays, said lever being normally heldagainst the back contact-screw, a, by its retractile spring, the tensionof which overcomes the magnetic attraction of the armature by therelay-magnet due to the weak normal line current. One pole of localbattery LB is connected by wire 1 with the front contactscrew, to, ofthis relay. The other pole of said battery is connected by wire 2 to oneend of helix sof the sounder S, the other end of which helix isconnected by wire 3 to armature-lever a. of the relay. Thearmature-lever b of the sounder plays between the insulated back stop,b, and the front contact-screw, b", and is connetted by wire 4 with wire1 at post 5. Front contact-screw, b", of the sounder is connected bywire 6 with wire 3 at post 7. The soundermagnet is wound with a secondhelix, 5, one end of which is connected by wire 8 with wire 2 at post 9,while the other end is connected by wire 10 with the armaturelever c ofthe subsidiary neutral relay SR, which is included in the line-circuit.The front contact-screw, c, of this subsidiary relay is connected bywire 11 with the back contact screw, (1?, of the receiving -re1ay HR.The subsidiary neutral relay is so adjustedthat its armature-lever 0will be held against the front contact-screw, 0, under allline-currents, and will be retracted by its retractile spring only whenthe line current vanishes, momentarily, during reversals. The helices sand s are wound on the core in opposite directions, and are of equalcapacity, so that the sounder-magnet is what is usually termed adifferential electro-magnet.

It will be observed that the sounder-magnet cannot be discharged unlessthe armature-lever 0 of the subsidiary neutral relay SR is inconsequently the sounder-magnet cannot be discharged, but continues thesignal. It will also be observed that the momentary retractions ofarmature-lever c at reversals when relay NR is not receiving have noinjurious effeet on the local circuit of said relay.

The use of helix 8 provides for a prompt discharge of thesounderanagnet; but said helix and wire 10 may be omitted, asillustrated in my aforesaid application, and post 9 connected by wire 8to armaturelever 0, so as to merely shunt the local current around thehelix 8.

I do not limitmyself to the herein-described special use of myinvention. For instance, the subsidiary neutral relay may be used inconnection with the local arrangement shown in United States Patent No.274,112, for controlling the local branch connected with the backcontact-screw of the receiving-relay.

I believe the feature of controlling a local branch by a subsidiaryrelay in the main-line circuit to be entirely new, and my first claim isdesigned to cover this feature as broadly as is possible within legalbounds. I claim as my invention 1. The combination, substantially asbefore v set forth, of a receiving-relay, a local circuit controlledthereby, a local branch for said local circuit, and a subsidiary relayin the main-line circuit for controlling said local branch.

2. The combination, substantially as before set forth, of a neutralreceivingrelay subject to rise and fall of tension as well as to rever-B. E. J. EILS.

IVitnesses:

O. A. N EALE, E. T. WVALKER.

